mod_jk 
Official Website
http://tomcat.apache.org/tomcat-3.3-doc/mod_jk-howto.htmlCategory
Web Server ExtensionsMod_jk is an Apache module used to connect the Tomcat servlet container with web servers such as Apache, iPlanet, Sun ONE (formerly Netscape) and even IIS using the Apache JServ Protocol. A web server waits for client HTTP requests.